The present invention relates to an apparatus for opening and further transporting folded printed products.
An apparatus of this type is disclosed in the older, later-published Swiss Patent Application No. 03 724/92-1. By means of transporting clips of a conveying device, folded printed products are held at the fold and transported while suspended. With their end region opposite the fold, they come into bearing contact with a supporting element, whereby the end region, seen in the conveying direction, is bent backward. An opening unit has a carrying element, which is designed in the manner of a star wheel. On the radial carrying arms of the star wheel grippers are arranged. The grippers have a gripper jaw, fastened on the carrying arm, and a gripper tongue interacting with the jaw and mounted on the carrying element. Openings in the gripper jaw and the gripper tongue on the active clamping side can be connected to a vacuum source. A gripper picks the printed product up from the rear supported in the border region. The product is then seized and held by closing of the gripper at the edge opposite the fold. Once the gripper moved along with the printed product has moved away out of the region of the supporting element, the gripper tongue is transferred into the open position. The two product parts are firmly held at the gripper tongue and gripper jaw, respectively, and lifted off from each other on account of the openings connected to the vacuum source. By disconnecting the opening of the gripper jaw from the vacuum source, the corresponding, lower product part is released. This product part is pushed-off from the gripper jaw by means of an angle lever which is mounted on the carrying element and carries at its end a stabbing element, stabbing between the printed products lifted off from each other. As a result, the printed product is further opened. A holding-open element engages between the two product parts, lifted off from each other, after which the opening of the gripper tongue is also disconnected from the vacuum source. In this document it is also mentioned that it is conceivable to open printed products with a leading end region by means of such an opening unit.
With this known device, the printed products are only slightly lifted off from each other, preopened, by the gripper jaws and gripper tongues acting like suction heads. The actual opening is performed by pushing the one product part off the gripper jaw by means of the stabbing element and angle lever. After the pushing off, consequently the pushed-off product part is no longer held, which may limit the permissible processing speed. Furthermore, during pushing off, the edge opposite the fold is acted upon, which could result in damage to the printed product. Moreover, the attainable opening of the printed product is restricted and the opening is not accessible along the entire edge.
Therefore, in view of the above, it is an object of the present invention to provide an apparatus for opening and further transporting folded printed products which, at great processing speed, allows opening which is reliable and gentle on the printed products and which permits at any desired location the inserting of a holding-open element between the product parts lifted off from each other.